FIX: use absolute url for `/user_avatar/` links

FIX: use absolute url for /user_avatar/ links

diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 598d37a..baee16f 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -502,6 +502,8 @@ module ApplicationHelper
       absolute_url = "#{Discourse.base_url}#{link}"
     elsif link.start_with?("/images/")
       absolute_url = "#{Discourse.base_url}#{link}"
+    elsif link.start_with?("/user_avatar/")
+      absolute_url = "#{Discourse.base_url}#{link}"
     elsif GlobalSetting.relative_url_root && link.start_with?(GlobalSetting.relative_url_root)
       absolute_url = "#{Discourse.base_url_no_prefix}#{link}"
     end

GitHub sha: c028e1ac